You are much better off installing Erlang and Elixir through asdf. After you do that, set up global and/or local (inside a project dir) versions and you should be good to go.

Oh, and to have the necessary tooling for downloading dependencies you should also run this after successful installations: mix local.rebar --force && mix local.hex --force.

I use asdf as well! It really helps pin the version to whatever we want for reproducible builds.

Here are the commands I use:

brew install asdf

asdf plugin-add elixir https://github.com/asdf-vm/asdf-elixir.git
asdf plugin-add erlang https://github.com/asdf-vm/asdf-erlang.git

asdf install

mix do local.hex, local.phx

asdf reshim elixir

Here’s the content of .tool-versions file, that needs to be in root of your project folder, for asdf to read:

P.S. Mix is a build tool that ships with Elixir that provides tasks for creating, compiling, testing your application, managing its dependencies and much more!!

Agree about asdf, if you’re on a Mac this guide may help